A magnetic sensor device equipped with a magnet and a magnetoresistive effect element is disclosed in Unexamined Japanese Patent Application Kokai Publication No. 2012-255770 (Patent Literature 1). This magnet generates an intersecting magnetic field that intersects a to-be-detected object. Further, this magnetoresistive effect element is arranged between the magnet and the to-be-detected object, has an output terminal, and outputs, as a change of resistance value, change of a conveyance direction component of the intersecting magnetic field due to a magnetic component of the to-be-detected object conveyed within the intersecting magnetic field. A configuration for generation of the intersecting magnetic field as disclosed in Patent Literature 1 includes a configuration in which magnets are arranged to oppose each other with the object therebetween and a configuration in which a magnet is arranged to oppose one surface of the object and a magnetic body is arranged to oppose another surface of the object.